Spinneret pack assembly



May 5, 1970 P.V.M. VAN DEN BIGGELAAR 3,509,593

srmnnnm max ASSEMBLY Filed April 17, 1967 INVENTOR.

PAUL V. M. VAN DEN BIGGELAAR United States Patent Office 3,509,598 Patented May 5, 1970 US. Cl. 18-8 2 Claims ABSTRACT OF THE DISCLOSURE An improved spinneret pack assembly for the melt spinning of synthetic filaments, fibers or yarns adapted to be completely sealed under polymer pressure with flange means supporting the distribution plate and the spinneret plate, respectively, against pressures imparted by the polymer.

This invention relates to new and useful apparatus for melt spinning synthetic filaments, fibers and yarns. More specifically, the invention relates to a spinneret assembly or pack used for the melt spinning of filaments, threads and yarns from thermoplastic materials such as polyamides, polyesters, polyolefins, glass, etc., and visualizes several novel improvements over apparatus known in the art which comprises a housing, a spinneret plate provided with shape imparting orifices supported by an outwardly extending shoulder portion of the housing, and wherein the spinneret plate, in turn, supports a distribution plate, polymer filter screens, supporting plates, etc., wherein polymer pressures are directly and indirectly exerted on one single housing shoulder which is adapted to support the plate, etc.

In general, the apparatus of the invention embodies improvements to that apparatus as shown in US. Patent No. 2,871,511. This patent depicts melt spinningapparatus comprising a spinneret assembly with some or all of its internal components being capable of limited relative movement when under the effect of polymer pressure. This is a unique approach to prevent polymer leakage in that the hydraulics of the liquid polymer within the pack supposedly act to close olf the joints between the various components held in the pack.

Several decided disadvantages have been observed in this type of construction, however. For example, in the construction contemplated by the patent, results of the forces acting on the spinneret plate, and including the above mentioned components supported thereby, are directly translated to and absorbed by a single housing shoulder supporting the plate. Such construction. is no longer practical in that there is a recent and significant trend in the art to greatly increase polymer viscosity in order to obtain higher performance filaments, fibers and yarns. Pressures encountered when spinning highly viscous polymers are significantly increased and oftentimes the constructions noW in use fail; Molten linear polymers currently being used for spinning high performance textile ma terials are highly viscous, slow flowing substances that cause pressures in the spinneret pack to reach as high as 200 to 500 kg./cm.

It is therefore a primary object of this invention to provide apparatus to be used in the melt spinning of highly viscous polymers capable of withstanding high polymer pressures.

Advantageously the present invention provides novel structure which avoids concentration of pressures that are encountered when spinning highly viscous polymers. Perhaps. more precisely, the construction avoids a pressure concentration at any one point or segment of the spinneret housing or any one assmebly component that is contained by the housing.

As therein described in greater detail, the invention contemplates a spinneret pack assembly for spinning highly viscous polymers wherein the distribution plate rests on a second flange located above a lower flange provided for the spinneret plate, per se. Both flanges are provided in the inner wall of the housing and with such an embodiment, the second flange absorbs approximately half the polymer pressure previously exerted on the single flange supporting all the spinneret components including the perforated platen With the present invention, pressures now exerted on the distribution plate are practically of the same order of magnitude of those polymer pressures being exerted on the spinneret plate. Hence, thetotal force exerted on the lower flange (and on the spinneret plate supported thereby) is much smaller than when all the pressure forces must be absorbed by a single lower flange as is characteristic of the prior art. Accordingly, a more uniform force distribution is attained.

Further in accordance with this invention, it has been found advantageous to lock the pack lid closure means utilizing a slide or key-lock type principle. This facilitates use of increased viscosity polymer and spinneret plate of larger size. According to the invention, the slide extends across the upper surface of the pack lid and through two opposed grooves in the side wall of the spinneret housing.

For the purposes of understanding the invention, reference is made to the accompanying drawings in which:

FIGURE 1 shows the spinneret pack assembly in cross section; and

FIGURE 2 showsthe assembly as FIGURE 1 in planned view and with particular emphasis on the unique lid locking means.

In FIGURE 1, reference numeral 1 refersto the spinneret packhousing provided with lower flange 2 on which spinneret plate 3 (having spinneret orifices 4) is positioned. Distribution plate ,5 is positioned immediately above spinneret plate 3 and is provided with several polymer distribution channels 6 machined therein. Theplate is seated on secondfla nge 7 machined into the inner wall of housing 1. Filter pack 8 is adapted for positioning on the top of distribution plate. 5. Outwardly extending shoulder-s10 of pack lid 9 areadapted to rest on housing 1. Lid 9 is provided with conduits 12 for themolten polymer being introduced to thespinneret assembly. Feed conduit 12 is connected to a polymer flow line 13 which passes through aheated jacket to a source of liquid polymer. supply (not shown). Polymer line 13 is made conveniently detachable from the spinneret assembly in order that the entire assembly can be. removed.

, ample, by a pressure of abolt (14) acting in a direction indicated by the arrow. Inside the assembly there are.

Lid 9 is provided with two lugs that are adapted to fit in grooves 11 of the housing in orderto complete sealing of the apparatus. The lid is retained infhousing 1 by means 1 of slide 15 which extends across the upper faceof the. lid. and through twoopposed grooves 16 and the top wall :of t the housing. The, joint between .ipolymer line 13 andicou duit 12 can "be sealed in. any convenientmanner, for extwo triangularly shapec. gaskets 20 which act to complete sealing within the assembly when influenced by the polymer pressure.

What is claimed is:

1. An improved spinneret assembly for melt spinning synthetic filaments, fibers and threads comprising in combination? (a) a housing with cover lid; said housing. having an inner wallwithupper'andilower annular flange means extending. therefrom,

(e) said distribution platebeing greater in diameter than i i said spinneret plate and having a plurality of polymer flow channels passing completely therethrough,

(i) said housnig being in fluid tight relationshipwith said distribution plate and said spinneret plate when influenced by polymer pressure,

(g) said spinneret assembly having means for deliver ing molten polymer thereto, and

the respective polymer pressures imparted thereto.

2. The apparatus of claim 1 in which said cover lid is secured by means of a slidable locking key extending across the top surface of said lid andthrough two oppo- 5 sitely opposed grooves in the Wall of said housing.

References Cited UNITED STATESPATBNTS 10 2,045,722

FOREIGN PATENTS 1,458,898 10/1966 France. 15 WILLIAM J. STEPHENSON, Primary Examiner supportingflsaid plates under i 6/1936 Pierrat et a1. "an 188 

